By vantal Establishment of distraction osteogenesis model of rat femur with fixatorAfter that, suture kit Not afraid of the future, dare to fight and fight, and won applause again and again in the market. https://pinnaclemedics.com/
In clinical research, the length of defect exceeding 2.0cm or the length of defect exceeding 50% of bone circumference is called critical bone defect, which is often difficult to heal itself. Bone transplantation with vascular pedicle, distraction osteogenesis, membrane-induced osteogenesis and tissue engineering are often used for treatment, or the above technologies are combined, but there are certain advantages and disadvantages.
Rat mouth gag
Ilizarov[0″ target=_blank> introduced Ilizarov technology in 1988. This technique is based on the theory of “tension-stress”, that is, the tension-stress generated by the continuous and steady stretching of the external fixation device can stimulate the proliferation and biosynthesis of the broken end cells of the bone defect, and the bone defect can be repaired by this method. This technique has the advantages of less trauma, no need for bone grafting, distraction osteogenesis and distraction of surrounding soft tissues. Clinically, it is often used to treat bone defect, nonunion, limb deformity and short stature.
However, Ilizarov technique still has some shortcomings, such as poor callus formation, nail infection, long course of treatment, affecting appearance, etc., and it takes a long time for new bone tissue to mature after operation, and the affected limb needs functional exercise, so that the treatment period is long, which will have a certain impact on the patient’s life and work, and long-term carrying of the fixation device will also have a certain impact on the patient’s physical and mental health; Launay et al. reported that during the stretching process, with the gradual stretching of muscles and tendons, joint flexion contracture and even dislocation may occur. Song et al. performed distraction osteogenesis on 34 patients with achondroplasia. After operation, 13 cases (38.2%) developed persistent flexion contracture deformity of hip joint, among which 8 cases (61.5%) developed limited knee flexion. Watson reported that during distraction osteogenesis, the new bone was weak and its mechanical properties were poor. In view of the above problems, scholars from all over the world have studied distraction osteogenesis technology, aiming at accelerating fracture healing and shortening mineralization time. However, the study of distraction osteogenesis technology needs a suitable animal model, so it is of great significance to establish a suitable animal model of distraction osteogenesis.
The common distraction osteogenesis animal models are goat, beagle and big-ear rabbit, and big-ear rabbit, rat fixator and mouse tibia distraction osteogenesis model. There are few reports on rat femoral distraction osteogenesis model. Our research group found that the rat femoral distraction osteogenesis model has short modeling time and high success rate, which is more convenient for scientific research. From April 2019 to September 2019, the right femur distraction osteogenesis model of SD rats was made in our laboratory, which provided a basis for further research.
Materials and methods
First, experimental animals
A total of 30 adult male SD rats (SPF grade) were provided by the Animal Center of Xinjiang Medical University [CertificateNo.: SYXK (New) 2018-0003″ target=_blank>, weighing 350-400 g.. All rats were kept in a suitable environment for one week before the operation, and all were kept in a single cage, and adequate food and clean drinking water were provided. In the course of the experiment, it was implemented in strict accordance with the standards of animal medical ethics in China and the laboratory of Animal Center of Xinjiang Medical University (ethical approval number: IACUC20150730-01).
Second, the main instruments and equipment
Rat fixator
1. Main instruments: distraction osteogenesis external fixation device, designed by Key Laboratory of Engineering and Technology College of Xinjiang University, mainly made of titanium alloy, with a length of 50.0 mm, a width of 10.0 mm and a height of 10.0 mm; The end contains a rotating nut, which is used with an internal square wrench. The internal square wrench can increase the tension gap by 0.5mm every 360 clockwise rotation. The external fixation device is matched with four 1.0×200.0 mm self-tapping threaded Kirschner pins, which are made of titanium alloy and have a terminal thread length of 12.0mm.. For the convenience of the following description, we mark the corresponding nail channel of the external fixation device and fix the rat frame.
2. Experimental reagents and equipment: surgical instruments, 5% chloral hydrate, 75% alcohol, 4% paraformaldehyde, phosphate buffer salt solution, hematoxylin dye solution, 1% hydrochloric acid ethanol, eosin aqueous solution, neutral resin, EDTA decalcification solution, X-ray machine, slicer, pendulum saw, etc.